Electric air purifier



June 18, 1963 B. BLANTON 3,094,400

ELECTRIC AIR PURIFIER Filed July 24, 1961 2 Sheets-Sheet 1 EN R.

w I v} James 5 j June 18, 1963 J. B. BLANTON 3,0

ELECTRIC AIR PURIFIER Filed July 24, 1961 2 Sheets-Sheet 2 IN VEN TOR.

Jim es Ji W7 BY JZWX United States Patent 3,094,400 ELECTRIC AIR PURIFIER James B. Blanton, Arlington Heights, Ill. Filed July 24, 1961, Ser. No. 126,085 Claims. (Cl. 55-102) The invention relates to improvements in the cons-truc tion and assembly of air purifiers and more particularly to a novel assembly designed to filter, purify, deodorize and add negative ions to air passing therethrough.

Air purifiers of the general character of the present invention utilize an excessive number of germicidal ultraviolet radiating iarnps to attain a desired level of efficiency and consequently are expensive to manufacture and maintain efficient. Known purifiers also rely primarily upon a substantially straight-through passage of air through the apparatus with the result that much of the dust or other solids in the air is borne into direct contact with the usual filters and tends to clog the interstices therein and reduce the volumetric flow of air therethrough and, of course, the efficiency thereof.

The air purifier embodying the present invention is designed to insure maximum efficiency with but a minimum number of germicidal lamps and also to cause air circulation in such paths as to insure maximum attraction of air borne particles without harmful accumulation of dust par: ticles on the filters. Further, the purifier herein disclosed is designed to confine ultra-violet radiation within the radiation chamber thereof and to prevent leakage of harmful radiation onto the filters and into exterior atmosphere. More particularly, the purifier herein disclosed admits air from without into the housing thereof through an electrostatic filter which removes much of the heavier airborne dust particles and the lighter particles passing through said filter are ionized and lightly charged. This prefiltering is of material assistance in reducing the likelihood of possible coating of the surfaces of the germicidal and ozone lamps therein with air borne contaminants and particles.

Pre-filtered air containing lightly charged particles is delivered into a radiation chamber and in such manner that it is broken up into what might be termed two columns or masses each moving through the radiation cham her in an opposite direction. The flow of each column or mass is handled in a manner so as to pass across a single germicidal ultra-violet lamp a minimum of from four to six and perhaps more times before leaving the radiation chamber. This multiple passage increases both time and exposure of the air mass to ultra-violet rays emanating from the germicidal lamp, thus further ionizing the airborne particles which now become highly charged. Such ionization or charging is essential to effective germ killing by ultra-violet energy. The highly charged airborne particles are repulsed by the lamp thus keeping the lamp clean for a prolonged period of time and in creasing its effectiveness. Accordingly, the instant arrangement, hereinafter described in detail, results in obtaining a high level of efficiency with minimum equipment and low operating cost.

The improved structure also includes an accumulation chamber wherein the two columns of ionized air leaving the radiation chamber are joined. The highly charged tiny airborne particles entering the accumulation chamber are attracted to each other and are induced to agglomerate. This agglomeration results in fewer but more highly charged particles being present in the accumulation chamber. The air leaving said accumulation chamber passes through a second electrostatic filter and, because of the high charge in the airborne particles, said filter functions as a precipitating unit and the charged particles are deposited thereon, instead of being drawn into the interstices thereof and blocking same.

As a result, the elec-" trostatic filters, which are removable, can be easily and quickly cleaned by washing or vacuum cleaning. Deodorization of the air passing through the structure is accomplished by providing one or more ozone lamps in the radiation chamber.

It is therefore an object of the invention to provide a novel air purifier structure and assembly.

Another object is to provide an air purifier with novel means to insure maximum exposure of air passing therethrough to ultra-violet rays emitted from a single source.

Another object is to provide novel means to cause air passing through an air purifying device to be repeatedly exposed to a single source of ultra-violet radiation as it advances therethrough.

Another object is to provide novel means to prevent the effect of radiation from reaching either one of the air filtering mediums in an air purifier.

Another object is to provide an air purifier with novel bafile means in the radiation chamber to insure maximum exposure to ultra-violet radiation.

Another object is to provide a novel passage for air flowing through a purifying device which is so designed as to divide the air flow into two distinct streams or masses for exposure to ultra-violet rays and which are subsequently brought together into a single mass before discharge through an electrostatic filter.

Another object is to provide a novelly constructed air purifying device which is not expensive to manufacture or maintain serviceable, is highly efi'icient in operation and which may be operated at minimum cost with maximum results.

With the foregoing and such other objects in view, which will appear as the description proceeds, the invention consists of certain novel features of construction, arrangement and combination of parts hereinafter fully described, illustrated in the accompanying drawings, and particularly pointed out in the appended claims, it being understood that various changes in form, proportion, size and minor details of the structure may be made without departing from the spirit of the invention.

Referring to the drawings in which the same characters of reference are employed to identify corresponding parts:

FIG. 1 is a perspective view of an air purifier unit em:

bodying the features of the invention.

FIG. 2 is a horizontal sectional view taken substantially on line 22 of FIG. 3.

FIG. 3 is a vertical sectional view substantially taken on line 3-3 of FIG. 2.

FIG. 4 is a transverse vertical sectional view taken substantially on line 4-4 of FIG. 3.

FIG. 5 is a schematic view showing the electric circuitry of the unit.

FIG. 6 is a diagrammatic view of the radiation chamber illustrating the deflection of the air stream passing therethrough and around the single germicidal lamp.

FIG. 7 is a detail sectional view of one of the two like filters.

Referring to the exemplary disclosure of the invention shown in the accompanying drawings, the air purifying. unit is housed in a substantially rectangular casing 11 including a front wall 12, bottom wall 13, top wall 14, back wall 15 and connecting end walls 16. A longitudinally elongated air inlet opening 17 is formed in front Wall 12 adjacent its lower edge and a filter element 18- is arranged rearwardly of said opening. Preferably, the filter element 18, best shown in FIG. 7, consists of a double panel plastic electrostatic filter having a space 19 between screens 20 to provide an accumulation compartment for airborne particles passing through the first or outer one of said filter screens.

Because air-borne dust and/ or other particles pick up an electrostatic charge during flotation the charged dust Patented June 18, 1963- is readily attracted to the self charged media of the electrostatic filter and much of said dust is removed from the air as it passes through the filter.

. Air containing the lightly charged particles passing through filter 18 enters the lower portion of bottom chamber 21 of casing 11 which has, as its top wall a horizontal partition 22 spaced substantially midway between and lying parallel with bottom and top walls 13 and 14 respectively.

Mounted within bottom chamber 21. is a blower fan assembly comprised of a motor 23 and a squirrel cage blower 24, the latter being enclosed in a housing 25 that has its air ingress opening 26 disposed toward but spaced inwardly from filter d8. Pre-filtered air from chamber 21 entering blower 24 is discharged radially upwardly through an outlet duct 27 that opens through horizontal partition 22 for discharge into a radiation chamber 28 located in the upper portion of casing 11.

The radiation chamber 28 constitutes but a portion of the upper compartment of housing the remaining portion of said upper compartment comprising an accumulation chamber 29. These two chambers are provided by means of a vertical partition 31 which extends from the horizontal partition 22 to the housing top wall 14 and is secured in place in any suitable manner. The vertical partition 31 extends longitudinally parallel with walls 12 and but terminates short of the housing end walls 16 in rearwardly turned end flanges 32. A second vertical wall 33, also bridging the space between horizontal partition 22 and top wall 14, is mounted closely adjacent to front wall .12. It has its end portions turned rearwardly to form inner end walls 34 and then inwardly longitudinally to define, with flanges 32, a pair of exhaust or outlet passageways 35, one leading from each end of radiation chamber 28 respective end regions of accumulation chamber 29.

A single germicidal ultra-violet radiating lamp 36 is arranged in the radiation chamber 28, said lamp extending the length thereof and being mounted in sockets 37 carried by inner end walls 34 so as to be disposed substantially centrally within the transverse cross section of said radiation chamber and bridging the outlet of duct 27.

Air and air-borne electrostatically charged particles discharged from duct 27 into chamber 28 is turbulated within said radiation chamber in a manner to cause it to have maximum exposure to the ultra-violet rays of the germicidal lamp before passing out through the end passageways 35 and into accumulation chamber 29'. This turbulence is accomplished by providing novel baflles or deflector elements 38-39 in said radiation chamber. As shown, baffle 38 is comprised of two parts, one located on each side of the outlet of duct 27 and seated on horizontal partition 22. Baflle 38 preferably has a multitude of longitudinally-upwardly inclined surfaces 38a extending transversely of chamber 28. The other baflie 3% is secured to the bottom surface of top wall 14 and it also is formed with a plurality of longitudinally-downwardly inclined surfaces 39a extending transversely of chamber 28.

It should be obvious that air entering radiation chamber 28 through duct 27 is divided into two separate streams one directed toward each end of chamber 28. These streams are agitated or turbulated, by flowing back and forth between baffles 3839, in such manner as to pass over and around the germicidal lamp 36 a large number of times thus materially increasing the elfectiveness of said lamp. Because much of the heavier air-borne dust is removed as the air passes through filter 18, coating of the germicidal lamp with dust is greatly minimized.

Comparative tests of apparatus having the above described radiation chamber and baffle arrangement and using one germicidal lamp with conventional apparatus using three or more germicidal lamps, and involving an air displacement of 145 cubic feet per minute, have established that the one germicidal lamp in the herein disclosed purifier produces a bacterial kill slightly greater than the bacterial kill obtained with an apparatus having four lamps. These tests were conducted without ozone and in an area protected from direct draft from the test unit. Elapsed time was four hours and the recorded bacterial kill, using lapplicants purifier was 92.04% whereas the prior known test apparatus using four lamps showed a bacterial kill of under identical conditions. Thus, it is established that the present unit, using one germicidal lamp under normal conditions of use is extremely effective and the danger from airborne contamination is greatly reduced.

Applicant adds to the efiiciency and usefulness of the unit by providing an ozone source preferably in the form of a plurality of ozone lamps 41 within the radiation chamber 28. As shown, four such lamps are provided and preferably they are connected with a current source in a manner to permit two or all four of said lamps to be energized at one time.

As previously stated the electrostatically charged turbulated air from the chamber 28 flows in two directions and it is discharged into the end regions of accumulation chamber 29 through passageways 35. These two columns of air join in chamber 29 and the highly charged particles therein are attracted to one another and agglomeration takes place. Otherwise stated, the tiny charged particles adhere one to the other to form larger particles or masses each of which now has a much higher than normal electrostatic charge.

Referring now particularly to FIG. 2, the air is exhausted from chamber 29 through a second electrostatic filter 42 mounted in back wall 15. This filter is identical to filter 18 and when the air passes therethrough, the filter functions as a precipitating element in that the large highly charged particles are deposited on the surface of electrostatic filter in the form of strings as distinguished from packing in and clogging the interstices of the filter. The particles accumulating on said filter maybe easily and quickly removed by withdrawing the filter from the unit and washing or vacuum cleaning same. Because ionization of the air occurs within the radiation chamber and no leakage of radiation from said chamber is possible, the filters are protected from such radiation and hence are not harmed thereby.

Switches 43-44 are mounted in a readily accessible position on cabinet v11, one operable to close the electric circuit to the blower motor and germicidal lamp and the other selectively operable to close the electrical circuit to two or all four of the ozone lamps. Signal lamps 45 may be connected in said circuits to afford visual means for determining when the system is in operation.

As many possible embodiments may be made in the invention, and as many changes might be made in the embodiments above set forth, it is to be understood that all matters hereinbefore set forth or shown in the accompanying drawings are to be'interpreted as illustrative and not in a limiting sense.

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent of the United States is:

1. In an air purifying apparatus, an elongated substantially rectangular housing, a partition dividing said housing into a lower chamber and an upper compartment, 2. vertical partition dividing the upper compartment into an elongated radiation chamber and an elongated accumulation chamber, an air ingress opening communicating directly with the interior of said lower chamber and an air egress opening in the accumulation chamber, a filter covering said ingress opening for preliminary removal of air-borne impurities from air passing into said lower chamber, a blower unit in said lower chamber having its air outlet duct opening into the central region of the radiation chamber, the ends of said radiation chamber being in flow communication with the respective ends of the accumulation chamber, a germicidal ultra-violet radiating unit in said radiation chamber and extending longitudinally substantially -the entire length of said radiation chamber, baffles in said radiation chamber to divert air entering same through said duct toward the ends of said radiation chamber, said baffles being effective to turbulate the air in said radiation chamber and to cause it to flow around the germicidal uni-t a multitude of times to maximize the radiation effect of the unit and effectively destroy undersirable organisms in the air, said accumulation chamber functioning to mix the ionized air flowing thereinto and cause charged particles therein to agglomerate, and a filter covering said egress opening.

2. In an air purifying apparatus, an elongated substantially rectangular housing, a partition dividing said housing into a lower chamber and an upper compartment, 3. vertical partition dividing the upper compartment into an elongated radiation chamber and an elongated accumulation chamber, an air ingress opening communicating directly with the interior of said lower chamber and an air egress opening in the accumulation chamber an electrostatic filter covering said ingress opening for preliminary removal of air-borne impurities from air passing into said lower chamber, a blower unit in said lower chamber having its air outlet duct opening into the central region of the radiation chamber, the ends of said radiation chamber being in flow communication with the respective ends of the accumulation chamber, a plurality of azone generating elements in said radiation chamber, a germicidal ultra-violet radiating unit in said radiation chamber and extending longitudinally substantially the entire length of said radiation chamber, baflies in said radiation chamber to divert air entering same through said duct towards the ends of the radiation chamber, said baffies being effective to turbulate the air in said radiation chamber and to cause it to flow around the germicidal unit a multitude of times to maximize the radiation effect on the unit and effectively destroy undesirable organisms in the air, said accumulation chamber functioning to mix the ionized air flowing thereinto and cause charged particles therein to agglomerate, and an electrostatic filter covering said egress opening.

3. In an air purifying apparatus of a type including an elongated substantially rectangular housing having an air ingress opening and an air egress opening, a partition dividing said housing into a lower chamber and an upper compartment, a vertical partition dividing the upper compartment into a radiation chamber and an accumulation chamber, said air ingress opening communicating directly with the interior of said lower chamber and an air egress opening communicating with the accumulation chamber, an electrostatic filter covering said ingress opening so as to effect preliminary removal of air-borne impurities from air passing into said lower chamber, a blower unit mounted in said lower chamber and having its air outlet in direct communication with the radiation chamber, said radiation chamber having an air outlet passageway at each end thereof, one in direct communication with each end of the accumulation chamber, an elongated germicidal ultra-violet radiating unit in said radiation chamber, said unit extending longitudinally substantially the entire length of said radiation chamber, baffles in said radiation ch amber to divert air entering same through said duct into separate streams some of which are directed in the general direction of the air outlet passageways at the ends of the radiation chamber, said baffles being effective to turbulate the air suficiently to cause it to flow around the germicidal unit a multitude of times before reaching the outlets to maximize the radiation effect of the unit on the air to effectively destroy undesirable organisms in the air delivered to the accumulation chamber in which the ionized air streams are joined to cause charged particles to agglomerate, and an electrostatic filter covering said egress opening.

4. In an air purifying apparatus of a type including an elongated substantially rectangular housing including a partition dividing said housing into a lower chamber and an upper compartment and a vertical partition dividing said upper compartment into a radiation chamber and an accumulation chamber, an air ingress opening communicatig directly with the interior of said lower chamber, an electrostatic filter covering said ingress opening so as to effect preliminary removal of airborne impurities from air passing into said lower chamber, a blower unit mounted in said lower chamber having its intake in direct communication with the lower chamber and its air outlet duct in direct communication with the radiation chamber, saidradiation chamber having an air outlet at each end thereof in direct communication with the accumulaton chamber, an elongated germicidal ultra-violet radiating unit in said radiation chamber, said unit bridging the air outlet duct and extending longitudinally substantially the entire length of said radiation chamber, means in said radiation chamber to divert air entering same through said duct into two streams one directed toward the air outlet at each end of the radiation chamber, said means being effective to turbulate the air in said streams so as to cause it to flow around the germicidal unit a plurality of times before reaching said end outlets to maximize the radiation effect of the unit on the air and effectively destroy undesirable organisms in the air, means for directing the streams of ionized air leaving said end outlets into the end regions of the accumulation chamber so that said columns are merged in said accumulation chamber to cause charged particles therein to agglomerate, an egress opening in said accumulation chamber, and an electrostatic filter covering said opening.

5. In an air purifying apparatus of a type including an elongated substantially rectangulm housing including a partition dividing said housing into a lower chamber and an upper compartment, a vertical partition dividing said upper compartment into a radiation chamber and an accumulation chamber, an air ingress opening communicating directly with the interior of said lower chamber, an electrostatic filter covering said ingress opening so as to effect preliminary removal of airborne impurities from air passing into said lower chamber, a blower unit mounted in said lower chamber and having its intake in direct communication with the lower chamber and its air outlet duct in direct communication with the radiation chamber, said radiation chamber having an air outlet at each end thereof in direct communication with the end regions of said accumulation chamber, an elongated germicidal ultraviolet radiating unit in said radiation chamber, said unit extending longitudinally substantially the entire length of said radiation chamber, baflles in said radiation chamber to divert air entering said radiation chamber into two main streams one directed in the general direction of the air outlet at each end of the radiation chamber, said baffles being effective to turbulate the air in said streams so as to cause it to flow around the germicidal unit a plurality of times before reaching the outlets to maximize the radiation effect on the air and effectively destroy undesirable organisms in the air, means for directing the streams of ionized air leaving said outlets into said accumulation chamber wherein they intermingle and cause charged particles thereof to agglomenate, an egress opening in said accumulation chamber, and an electrostatic filter covering said opening.

6. An electric air purifyer comprising a substantially rectangular housing including a partition dividing the interior thereof into a lower and an upper chamber, partition means dividing said upper chamber into a radiating chamber and an accumulating chamber, an air ingress opening communicating directly with said lower chamber, a filter covering said air ingress opening, a blower shroud in said lower chamber having an intake port disposed toward but spaced from said filter and an air outlet port in direct communication with the radiating chamber, said .outlet port being located substantially midway the length of said radiating chamber, a blower mounted in said shroud, an outlet passageway at each end of said radiating chamber, a germicidal ultra-violet radiating lamp in said radiating chamber, biafiies in said radiating chamber to deflect air flowing thereinto into separate streams one flowing in the general direction of each outlet passageway and to turbulate said air streams so as cause them to pass over and around said germicidal lamp a plurality of times before reaching said outlet passageways, said passageways being shaped to deliver air flowing therefrom into opposite ends of the accumulating chamber, said accumw lating chamber having an air egress opening, and a filter covering said egress opening.

7. The air purifier recited in claim 6 in which the germicidal lamp extends across the blower shroud outlet port and is substantially coextensive with the length of the said second chamber so that maximum radiation of air flowing through said second chamber is efiected.

8. The air purifier recited in claim 6, in which the end outlet passageways from the radiating chamber comprise ducts projecting into the end areas of the accumulation chamber and having their outlets disposed inwardly one toward the other.

9. The air purifier recited in claim 6 in which the filters are fabricated from electrostatic material.

10. The air purifier recited in claim 9 in which the filters are each comprised of at least two layers of electrostatic material spaced apart to define a collection space between them.

References Cited in the file of this patent UNITED STATES PATENTS Great Britain Dec. 14, 1960 

1. IN AN AIR PURIFYING APPARATUS, AN ELONGATED SUBSTANTIALLY RECTANGULAR HOUSING, A PARTITION DIVIDING SAID HOUSING INTO A LOWER CHAMBER AND AN UPPER COMPARTMENT, A VERTICAL PARTITION DIVIDING THE UPPER COMPARTMENT INTO AN ELONGATED RADIATION CHAMBER AND AN ELONGATED ACCUMULATION CHAMBER, AN AIR INGRESS OPENING COMMUNICATING DIRECTLY WITH THE INTERIOR OF SAID LOWER CHAMBER AND AN AIR EGRESS OPENING IN THE ACCUMLATION CHAMBER, A FILTER COVERING SAID INGRESS OPENING FOR A PRELIMINARY REMOVAL OF AIR-BORNE IMPURITIES FROM AIR PASSING INTO SAID LOWER CHAMBER, A BLOWER UNIT IN SAID LOWER CHAMBER HAVING ITS AIR OUTLET DUCT OPENING INTO THE CENTRAL REGION OF THE RADIATION CHAMBER, THE ENDS OF SAID RADIATION CHAMBER BEING IN FLOW COMMUNICATION WITH THE RESPECTIVE ENDS OF THE ACCUMULATION CHAMBER, A GERMICIDAL ULTRA-VIOLET RADIATING UNIT IN SAID RADIATION CHAMBER AND EXTENDING LONGITUDINALLY SUBSTANTIALLY THE ENTIRE LENGTH OF SAID RADIATION CHAMBER, BAFFLES IN SAID RADIATION CHAMBER TO DIVERT AIR ENTERING SAME THROUGH SAID DUCT TOWARD THE ENDS OF SAID RADIATION CHAMBER, SAID BAFFLES BEING EFFECTIVE TO TURBULATE THE AIR IN SAID RADIATION CHAMBER AND TO CAUSE IT TO FLOW AROUND THE GERMICIDAL UNIT A MULTITUDE OF TIMES TO MAXIMIZE THE RADIATION EFFECT OF THE UNIT AND EFFECTIVELY DESTROY UNDESIRABLE ORGANISMS IN THE AIR, SAID ACCUMULATION CHAMBER FUNCTIONING TO MIX THE IONIZED AIR FLOWING THEREINTO AND CAUSE CHARGED PARTICLES THEREIN TO AGGLOMERATE, AND A FILTER COVERING SAID EGRESS OPENING. 